Oracle Oracle Certifications 1Z0-902 Questions & Answers

• Question 41:

  Which are three customer options for hosting the Platinum Services Advanced Support Gateway?

  A. Install on Oracle Database Appliance.

  B. Provide individual x86 64-Bit gateway hardware.

  C. Install in Oracle Virtual Machine with required hardware.

  D. Purchase the recommended x86 64-Bit gateway hardware from Oracle.

  E. Install on Exadata Engineered System.

  Correct Answer: ABD

  Explanation: According to Oracle's documentation1, the customer options for hosting the Platinum Services Advanced Support Gateway are: Provide individual x86 64-Bit gateway hardware1 Purchase the recommended x86 64-Bit gateway hardware from Oracle1 Install on Oracle Database Appliance2

• Question 42:

  Your customer needs to ensure that their data is available on the Exadata machine during updates. The customer wants to be able to update one server at a time but still be protected against single-node server failure.

  What ASM redundancy level should they use?

  A. Normal

  B. Sparse

  C. High

  D. External

  E. Extended

  Correct Answer: A

  Your customer needs to ensure that their data is available on the Exadata machine during updates. The customer wants to be able to update one server at a time but still be protected against single-node server failure. This means that they need a redundancy level that can tolerate at least one disk failure without losing data availability or performance. Therefore, the best option for them is normal redundancy . Normal redundancy provides two-way mirroring by default, which means that each data extent has a primary copy and a mirror copy on different disks in different failure groups1. A failure group is a subset of disks within a disk group that are likely to fail at the same time due to common dependencies2. On Exadata Database Machine , each Storage Server is considered as a failure group by default2. This means that if one Storage Server fails or needs to be updated , the data on its disks can still be accessed from another Storage Server that has the mirror copies of the same data extents2. Therefore, normal redundancy ensures data availability and performance during updates or single-node server failures. https://docs.oracle.com/en/engineered-systems/exadata-databasemachine/sagug/exadata-administering-asm.html

• Question 43:

  Which three steps are required to expand an Exadata X9M-2 Database Server with the lowest memory configuration available to the highest memory configuration?

  A. Add 12x 32GB DIMMs.

  B. Add 12x 64GB DIMMs.

  C. Shutdown the Database Server if running.

  D. Add 16x 32GB DIMMs.

  E. Add 16x 64GB DIMMs.

  F. Memory cannot be expanded on Exadata X9M-2 Database Servers.

  G. Remove existing memory modules.

  H. Add 32x 64GB DIMMs.

  I. Add 24x 32GB DIMMs.

  Correct Answer: CGH

  Explanation: https://www.oracle.com/a/ocom/docs/engineered-systems/exadata/exadata- x9m-2-ds.pdf

  https://chriscraftoracle.wordpress.com/2022/11/09/what-makes-exadata-faster/

• Question 44:

  Which statement is true about the Persistent Memory Commit Accelerator?

  A. Persistent Memory Commit Accelerator tracks changes to Persistent Memory Data Accelerator to ensure duplicate blocks are not written to Flash.

  B. Persistent Memory Commit Accelerator helps to further reduce redo log write latency by using Persistent Memory and Remote Direct Memory Access (RDMA).

  C. Persistent Memory Commit Accelerator copies redo log data from disk for faster redo apply on Data Guard Standby Databases.

  D. Persistent Memory Commit Accelerator contains logging information from all tiers of the software stack for rapid triage and diagnostics.

  E. Persistent Memory Commit Accelerator reduces redo log write latency by using Persistent Memory and RDMA before flushing to Flash then disk.

  Correct Answer: B

  Explanation: https://docs.oracle.com/en/engineered-systems/exadata-database- machine/dbmso/new-features-exadata-system-software-release-23.html

• Question 45:

  You are adding a disk expansion kit to a running Exadata X8M Database Machine's Database Servers, and have a filesystem layout that includes:

  

  After running the following commands, which command needs to be run to add 20G of space to the filesystem mounted on /u01?

  

  A. # lvextend -L +20G --verbose /dev/mapper/VGExaDb-LVDbOral

  B. # xfs_growfs /uOl +20G

  C. # resize2fs +20G /dev/VGExaDb/LVDbOral

  D. # lvextend -L +20G --verbose /dev/VGExaDb/LVDbOral

  Correct Answer: A

  Explanation: After running the commands above, the filesystem mounted on /u01 is on the logical volume /dev/mapper/VGExaDb-LVDbOral. So, to add 20G of space to the filesystem mounted on /u01, the command that needs to be run is: lvextend -L +20G --verbose /dev/mapper/VGExaDb-LVDbOralThis command will extend the logical volume /dev/mapper/VGExaDb-LVDbOral by 20 GB of space. It is important to note that the option --verbose is used to display the progress of the operation.

• Question 46:

  You have been asked by Oracle Support to check the firmware of the hard and flash disks in a storage server. Which cellcli command should you use to get this information?

  A. list celldisk attributes name, deviceName, diskType, physicalFirmware

  B. list cell attributes name, deviceName, diskType, physicalFirmware

  C. list physicaldisk attributes name, deviceName, diskType, physicalFirmware

  D. list devices attributes name, deviceName, diskType, physicalFirmware

  Correct Answer: C

  Explanation: This command will display the name, deviceName, diskType and physicalFirmware attributes of the physicaldisks in a storage server, as explained in the Oracle Exadata Database Machine X9M Implementation Essentials Official Text Book (page 85). https://docs.oracle.com/en/engineered-systems/exadata-database- machine/sagug/exadata-storage-server-cellcli.html

• Question 47:

  Which two statements are false about backup to ZFS Storage Appliance (ZFSSA)?

  A. ZFSSA may connect directly to the Exadata 100Gb RoCE network switches.

  B. Top of Rack (ToR) switches are managed as part of the hardware stack and software levels are upgraded during the patching process.

  C. When backing up multi-rack systems, sharing Exadata X9M switches is recommended.

  D. ZFS Snapshots can provide rapid cloning of development and test environment.

  Correct Answer: AC

  Explanation: A. ZFS Storage Appliance (ZFSSA) can't connect directly to the Exadata 100Gb RoCE network switches. ZFSSA uses Fibre Channel protocol to connect to the Exadata storage cells. C. When backing up multi-rack systems,

  sharing Exadata X9M switches is not recommended. Each rack should have its own switches to minimize the risk of data loss due to switch failure.

  Review the safety guidelines.

  Unpack Oracle Exadata Rack.

  Let the Exadata acclimatize for 24 hours.

  Place Exadata in its allocated space.

  Stabilize the Exadata Rack.

  Power on Exadata PDU A.

  Power on Exadata PDU B.

  This order ensures that the necessary safety precautions are taken before installing the Exadata Database Machine, and that the machine is allowed to acclimate to its new environment before being powered on.

• Question 48:

  Which two statements are true about the initial storage configuration after the standard (non-virtualized) deployment of a new Exadata Database Machine with High Capacity storage servers?

  A. The sparse_ diskgroup is created automatically.

  B. There is free space available on the hard disks inside the database servers for possible extension of the /uoi file system.

  C. The DATA_ and RECO_ ASM diskgroups are built on with DATA on the outer-most tracks and RECO on the inner-most tracks of the physical disk.

  D. There is free space available on flashdisks inside the Exadata storage servers for possible use for storage indexes.

  E. There is free space available on flashdisks inside the Exadata storage servers to configure Exadata Smart Flash Logs.

  Correct Answer: DE

  Explanation: According to the Oracle Exadata Database Machine Technical Architecture1 , the initial storage configuration after the standard (non-virtualized) deployment of a new Exadata Database Machine with High Capacity storage servers includes two ASM disk groups: DATA_ and RECO_. These disk groups are built on hard disks and flash disks inside the Exadata Storage Servers1. The correct statements about this configuration are: Option D: There is free space available on flashdisks inside the Exadata storage servers for possible use for storage indexes. Storage indexes are a feature of Exadata Storage Software that can improve query performance by avoiding unnecessary I/O operations. Storage indexes use a small amount of flash memory to store metadata about data blocks stored on disk1. Option E: There is free space available on flashdisks inside the Exadata storage servers to configure Exadata Smart Flash Logs. Exadata Smart Flash Logs are another feature of Exadata Storage Software that can improve database performance by using flash memory as an extension of the database redo log buffer. This can reduce latency and increase throughput for redo log writes1.

• Question 49:

  Which three statements are true about the CELLCLI command?

  A. It can execute commands on multiple storage servers in parallel.

  B. It has command-line history.

  C. It requires root privileges to create CELLDISKS and GRIDDISKS.

  D. It can be executed on storage servers.

  E. It can be executed using the DCLI utility.

  Correct Answer: BDE

  The statements that are true about the CellCLI command are:

  It has command-line history . According to 1, you can use the up and down arrow keys to scroll through previous commands that you entered in CellCLI . You can also use Ctrl+R to search for a previous command by entering part of it . It can

  be executed on storage servers . According to 1, you can invoke CellCLI by logging in to the Exadata cell as cellmonitor , celladmin , or root user and typing "cellcli" . Within CellCLI , you can perform various management and monitoring tasks

  for the cell134.

  It can be executed using the DCLI utility . According to 5, DCLI (distributed CLI) is another utility that can be used to execute scripts and commands across multiple storagecells from a single interface. You can use DCLI to run CellCLI

  commands on multiple cells at once54.

• Question 50:

  You want to monitor how a large production table is accessed. Especially, you are interested to see how the access on that particular table leverages the benefits of the Exadata Platform.

  Which two actions are NOT appropriate for that purpose?

  A. YOU query VSSYSTEM_EVENTS and filter for the event 'cell physical IO interconnect bytes returned by smart scan', associated to your table.

  B. You query v$segment_statistics and filter for the Object ID of your table from dba_objects and the the column STATISTIC_NAME='optimized physical reads'.

  C. You query v$SYSTAT and filter for the statistic 'cell smart table scan', associated to your table.

  D. You run the CellCli-command list activerequest , filtering for the attributes ioReason and objectNumber, that you specify as 'Smart Scan' and the Object ID of your table from DBA_OBJECTS.

  Correct Answer: AC

  A. YOU query VSSYSTEM_EVENTS and filter for the event `cell physical IO interconnect bytes returned by smart scan', associated to your table. This does not show how much data was filtered by Smart Scan, but only how much data was returned after Smart Scan12.

  C. You query v$SYSTAT and filter for the statistic `cell smart table scan', associated to your table. This does not show how much data was filtered by Smart Scan for a specific table, but only for all tables in a session12. https:// www.databasejournal.com/oracle/monitoring-smart-scans-in-oracle-exadata/